Alkermes to Present New Data on Alixorexton and LUMRYZ® (sodium oxybate) at Sleep Europe 2026, Underscoring Leadership in Sleep Medicine Research

For best results when printing this announcement, please click on link below: Alkermes to Present New Data on Alixorexton and LUMRYZ(®) (sodium oxybate) at Sleep Europe 2026, Underscoring Leadership in Sleep Medicine Research — Data From Vibrance-1 Phase 2 Study Lancet Neurology Publication Evaluating Alixorexton in Narcolepsy Type 1 and Additional Data From Long-Term Extension Study in Narcolepsy Type 1 and Type 2 to be Shared in Oral Presentation — — Detailed Positive Results From REVITALYZ(SM) Phase 3 Study Evaluating LUMRYZ in Adults With Idiopathic Hypersomnia to be Shared in Oral Presentation — Alkermes plc (Nasdaq: ALKS) today announced plans to present two oral presentations and six posters from its industry-leading portfolio of sleep medicine research at the European Sleep Research Society’s (ESRS) 28(th) Congress, Sleep Europe 2026, taking place Oct.

20-23, 2026 in Maastricht, the Netherlands. The company will present new data related to LUMRYZ(®) (sodium oxybate) extended-release oral suspension, now part of Alkermes’ sleep portfolio following the acquisition of Avadel Pharmaceuticals plc, and alixorexton, Alkermes’ novel, investigational, oral, selective orexin 2 receptor (OX2R) agonist in development for the treatment of narcolepsy type 1 (NT1), narcolepsy type 2 (NT2) and idiopathic hypersomnia (IH). In an oral presentation, the company will present findings from the Vibrance—1 phase 2 study of alixorexton in adults with NT1, which were recently published in The Lancet Neurology ( ).

The presentation will also include data from the open-label, long-term extension study evaluating the safety and durability of effect in participants with NT1 and NT2 who received alixorexton for up to nine months of treatment. “I am pleased to present results from the Vibrance-1 phase 2 study and long-term extension evaluating alixorexton in patients with narcolepsy type 1 and type 2 at Sleep Europe. , Neurologist, Director of the Narcolepsy Center at the IRCCS of the Neurological Sciences of Bologna and Professor of Childhood Neuropsychiatry at the University of Modena and Reggio Emilia.

In a separate oral presentation and corresponding poster presentation within the “Impactful Clinical Trial” session, the company will share detailed results from the phase 3 REVITALYZ study evaluating the investigational use of LUMRYZ in adults with IH. The Company previously announced positive topline results for this study. “I am honored to present results from the REVITALYZ phase 3 trial evaluating LUMRYZ in adults with idiopathic hypersomnia, a chronic neurological disorder for which there are limited treatment options. , FCCP, FAASM, Principal of Bogan Sleep Consultants, LLC and Associate Clinical Professor at the University of South Carolina School of Medicine.

Additional highlights to be shared in poster presentations at Sleep Europe 2026 include: Results from an interim analysis of the ongoing open-label, long-term extension (LTE) study evaluating the safety and maintenance of effect of alixorexton in adults with NT1 and NT2 at week 24 of the LTE, approximately nine months after the first dose for participants treated with alixorexton in the randomized double-blind period of the Vibrance-1 and Vibrance-2 phase 2 studies; Exploratory findings from the Vibrance-2 phase 2 study evaluating the impact of alixorexton compared to placebo on patient-reported measures of cognition and fatigue in adults with NT2; Detailed study designs and methods for the Brilliance Studies, a phase 3 clinical trial program evaluating the safety and efficacy of alixorexton compared to placebo in adults with NT1 and NT2; and Findings from REFRESH, a prospective multicenter, real-world study in adults with narcolepsy, including patients who switched to LUMRYZ from a twice-nightly oxybate and patients new to oxybate treatment or returning to oxybate treatment after previously discontinuing a twice-nightly oxybate.

“The breadth of data being presented by Alkermes at Sleep Europe 2026 reflects both the strength of our research programs and our leadership in the field of sleep medicine. D. (MBChB), Chief Medical Officer and Executive Vice President, Research & Development at Alkermes. , FCCP, FAASM, Principal of Bogan Sleep Consultants, LLC and Associate Clinical Professor at the University of South Carolina School of Medicine Presentation Date: The oral presentation is scheduled to occur on Friday, Oct.

” The corresponding poster (F314) will be presented on Friday, Oct. 23, 2026 from 12:30—13:30 CEST. , Head of the Sleep Center at the Institute of Neurological Sciences of Bologna, Italy and Chair of Child Neurology at the University of Modena and Reggio Emilia Presentation Date: The oral presentation is scheduled to occur on Friday, Oct. 23, 2026 from 15:55—16:15 CEST as part of the “Hot Topics in Sleep Science and Medicine” session.

, Professor of Neurology and Physiology, and Director of the Sleep-Wake Disorders Center at the University of Montpellier, France, and Coordinator of the French National Reference Center for Rare Diseases dedicated to narcolepsy and hypersomnia Presentation Date: The poster will be presented on Friday, Oct. 23, 2026 from 12:30—13:30 CEST. , FCCP, FAASM, Principal of Bogan Sleep Consultants, LLC and Associate Clinical Professor at the University of South Carolina School of Medicine Presentation Date: The poster will be presented on Wednesday, Oct. 21, 2026 from 12:30—13:30 CEST.

, Alkermes Presentation Date: Presentation Date: The poster will be presented on Wednesday, Oct. 21, 2026 from 12:30—13:30 CEST. , Alkermes Presentation Date: The poster will be presented on Wednesday, Oct. 21, 2026 from 12:30—13:30 CEST.

, Florida Sleep Specialists Presentation Date: The poster will be presented on Thursday, Oct. 22, 2026 from 12:30—13:30 CEST. About Alixorexton Alixorexton (formerly referred to as ALKS 2680) is a novel, investigational, oral, selective orexin 2 receptor (OX2R) agonist in development for the treatment of narcolepsy type 1 (NT1), narcolepsy type 2 (NT2) and idiopathic hypersomnia (IH). (2) Once-daily oral administration of alixorexton was previously evaluated in a phase 1 study in healthy volunteers and patients with NT1, NT2 and IH, and in Vibrance-1 and Vibrance-2, phase 2 studies in patients with NT1 and NT2, respectively.

Alixorexton is currently being evaluated in the phase 3 Brilliance Studies in patients with NT1 and NT2, and in the phase 2 Vibrance-3 study in patients with IH. S. Food and Drug Administration (FDA) has granted alixorexton Breakthrough Therapy designation for the treatment of NT1 and Orphan Drug Designation (ODD) for the treatment of IH. The European Commission has granted ODD to alixorexton for the treatment of narcolepsy.

About LUMRYZ(®) (sodium oxybate) for extended-release oral suspension LUMRYZ (sodium oxybate) for extended-release oral suspension is a central nervous system depressant indicated for the treatment of cataplexy or excessive daytime sleepiness (EDS) in patients 7 years of age and older with narcolepsy. LUMRYZ is not currently approved by regulatory authorities for the treatment of idiopathic hypersomnia (IH).

Pursuant to the terms of a previously disclosed settlement and license agreement, Alkermes may not market, offer for sale, take orders for, distribute, promote, or provide patient support services with respect to LUMRYZ for IH before March 1, 2028, even if LUMRYZ were to receive FDA approval for IH prior to that date. IMPORTANT SAFETY INFORMATION WARNING: CENTRAL NERVOUS SYSTEM (CNS) DEPRESSION and ABUSE AND MISUSE Central Nervous System Depression LUMRYZ(®) (sodium oxybate) is a CNS depressant. Clinically significant respiratory depression and obtundation may occur in patients treated with LUMRYZ at recommended doses.

Many patients who received LUMRYZ during clinical trials in narcolepsy were receiving CNS stimulants. Abuse and Misuse LUMRYZ (sodium oxybate) is the sodium salt of gamma-hydroxybutyrate (GHB). Abuse or misuse of illicit GHB, either alone or in combination with other CNS depressants, is associated with CNS adverse reactions, including seizure, respiratory depression, decreased consciousness, coma, and death. Because of the risks of CNS depression and abuse and misuse, LUMRYZ is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the LUMRYZ REMS.

Contraindications LUMRYZ is contraindicated for use in: combination with sedative hypnotics or alcohol patients with succinic semialdehyde dehydrogenase deficiency Warnings And Precautions Central Nervous System Depression The concurrent use of LUMRYZ with other CNS depressants, including but not limited to opioid analgesics, benzodiazepines, sedating antidepressants or antipsychotics, sedating antiepileptic drugs, general anesthetics, muscle relaxants, and/or illicit CNS depressants, may increase the risk of respiratory depression, hypotension, profound sedation, syncope, and death.

If use of these CNS depressants in combination with LUMRYZ is required, dose reduction or discontinuation of one or more CNS depressants (including LUMRYZ) should be considered. In addition, if short-term use of an opioid (eg, post- or perioperative) is required, interruption of treatment with LUMRYZ should be considered. After first initiating treatment and until certain that LUMRYZ does not affect them adversely (eg, impair judgment, thinking, or motor skills), caution patients against engaging in hazardous activities requiring complete mental alertness or motor coordination such as operating hazardous machinery, including automobiles or airplanes.

Also caution patients against engaging in these hazardous activities for at least six (6) hours after taking LUMRYZ. Patients should be queried about CNS depression-related events upon initiation of LUMRYZ therapy and periodically thereafter. Abuse and Misuse LUMRYZ is a Schedule III controlled substance. The active ingredient of LUMRYZ, sodium oxybate, is the sodium salt of gamma-hydroxybutyrate (GHB), a Schedule I controlled substance.

Abuse of illicit GHB, either alone or in combination with other CNS depressants, is associated with CNS adverse reactions, including seizure, respiratory depression, decreases in the level of consciousness, coma, and death. The rapid onset of sedation, coupled with the amnestic features of GHB, particularly when combined with alcohol, has proven to be dangerous for the voluntary and involuntary user (eg, assault victim). Physicians should carefully evaluate patients for a history of drug abuse and follow such patients closely.

Lumryz Rems LUMRYZ is available only through a restricted distribution program called the LUMRYZ REMS because of the risks of central nervous system depression and abuse and misuse. Notable requirements of the LUMRYZ REMS include the following: Healthcare providers who prescribe LUMRYZ are specially certified. LUMRYZ will be dispensed only by pharmacies that are specially certified. LUMRYZ will be dispensed and shipped only to patients who are enrolled in the LUMRYZ REMS with documentation of safe use conditions.

Further information is available at or by calling 1-877-453-1029. Respiratory Depression and Sleep-Disordered Breathing LUMRYZ may impair respiratory drive, especially in patients with compromised respiratory function. In overdoses of oxybate with illicit use of GHB, life-threatening respiratory depression has been reported. Increased apnea and reduced oxygenation may occur with LUMRYZ administration.

A significant increase in the number of central apneas and clinically significant oxygen desaturation may occur in patients with obstructive sleep apnea treated with LUMRYZ. Prescribers should be aware that sleep-related breathing disorders tend to be more prevalent in obese patients, in men, in postmenopausal women not on hormone replacement therapy, and among patients with narcolepsy. Depression and Suicidality Depression, and suicidal ideation and behavior, can occur in patients treated with LUMRYZ.

In an adult clinical trial in patients with narcolepsy (n=212), there were no suicide attempts, but one patient with a history of depression and anxiety developed suicidal ideation in the LUMRYZ-treated group. In a clinical trial in pediatric narcolepsy patients administered immediate-release sodium oxybate, one patient experienced suicidal ideation and two patients reported depression. The emergence of depression in patients treated with LUMRYZ requires careful and immediate evaluation. Patients with a previous history of a depressive illness and/or a suicide attempt should be monitored carefully for the emergence of depressive symptoms while taking LUMRYZ.

Other Behavioral or Psychiatric Adverse Reactions Other behavioral and psychiatric adverse reactions can occur in patients taking LUMRYZ. During adult clinical trials in patients with narcolepsy administered LUMRYZ, 2% of 107 patients treated with LUMRYZ experienced a confusional state. No patients treated with LUMRYZ discontinued treatment because of confusion. 5% of 107 patients treated with LUMRYZ in the adult trial in patients with narcolepsy.

Other psychiatric reactions reported in adult clinical trials in patients with narcolepsy administered LUMRYZ included irritability, emotional disorder, panic attack, agitation, delirium, and obsessive thoughts. Other neuropsychiatric reactions reported in adult clinical trials in patients with narcolepsy administered immediate-release sodium oxybate and in the postmarketing setting for immediate-release sodium oxybate include hallucinations, paranoia, psychosis, aggression, and agitation. In a clinical trial in pediatric patients administered immediate-release sodium oxybate, neuropsychiatric reactions including acute psychosis, confusion, and anxiety were reported.

The emergence or increase in the occurrence of behavioral or psychiatric events in patients taking LUMRYZ should be carefully monitored. Parasomnias Parasomnias can occur in patients taking LUMRYZ. Sleepwalking, defined as confused behavior occurring at night and at times associated with wandering, was reported in 3% of 107 adult patients with narcolepsy treated with LUMRYZ. No patients treated with LUMRYZ discontinued due to sleepwalking.

Episodes of sleepwalking should be fully evaluated and appropriate interventions considered. Use in Patients Sensitive to High Sodium Intake LUMRYZ has a high sodium content. In patients sensitive to sodium intake (eg, those with heart failure, hypertension, or renal impairment), consider the amount of daily sodium intake in each dose of LUMRYZ. Most Common Adverse Reactions Most common adverse reactions (incidence ≥5% and greater than placebo) reported for any dose of LUMRYZ in a trial of adults with narcolepsy were nausea, dizziness, enuresis, headache, and vomiting.